demitri_hill
Oh, barnacles!
This photo depicts a cluster of barnacles (Cirripedia) on a pier support column near Wrightsville Beach, Wilmington, NC on March 26th, 2017. There are currently more than 1,400 species of barnacles that have been identified, but the most common ones, or rather those that we're most familiar with, can be found on the undersides of boats or, in this case, underneath piers. Barnacles are generally harmless crustaceans due to most species being filter feeders. Some species, however, are parasitic, and benefit at the expense of another organism. A quintessential example of a parasitic barnacle belongs to the genus Sacculina. These barnacles attach themselves to the undersides of crabs and prevent the crab from reproducing or molting while deriving nutrients from the host. Unlike most barnacles, which are hermaphroditic, Cirripedia Sacculina is dioecious, meaning the male and female reproductive organs are located on separate individuals. Many species of barnacle, such as the one pictured above, prefer habitats with a lot of activity. The columns underneath the pier are located in the intertidal zone, the section of the coastal ecosystem that is both submerged and above water depending on tide level, is one of these habitats, and acts as an ideal location for barnacles to settle. During high tide, barnacles open their shells and filter the water for food with their legs. When the tide goes out, barnacles close their shells to conserve moisture. Barnacles mostly eat plankton, and are rarely preyed upon in their adult forms, as their shell protects them from most predators (except humans, which eat them in Spain and Portugal primarily). In their juvenile forms, however, barnacles are free floating (prior to settling on a surface), and have numerous predators. Reproduction is simple, and requires the fertilization of a nearby barnacle. A retractable tube is extended to fertilize the other barnacle, and newborn barnacles are released to feed, grow and eventually settle on a new surface.
(a-z-animals.com/animals/barnacle/)
(<a href="https://www.whoi.edu/science/B/people/kamaral/Barnacles.html")
(en.wikipedia.org/wiki/Sacculina)
Oh, barnacles!
This photo depicts a cluster of barnacles (Cirripedia) on a pier support column near Wrightsville Beach, Wilmington, NC on March 26th, 2017. There are currently more than 1,400 species of barnacles that have been identified, but the most common ones, or rather those that we're most familiar with, can be found on the undersides of boats or, in this case, underneath piers. Barnacles are generally harmless crustaceans due to most species being filter feeders. Some species, however, are parasitic, and benefit at the expense of another organism. A quintessential example of a parasitic barnacle belongs to the genus Sacculina. These barnacles attach themselves to the undersides of crabs and prevent the crab from reproducing or molting while deriving nutrients from the host. Unlike most barnacles, which are hermaphroditic, Cirripedia Sacculina is dioecious, meaning the male and female reproductive organs are located on separate individuals. Many species of barnacle, such as the one pictured above, prefer habitats with a lot of activity. The columns underneath the pier are located in the intertidal zone, the section of the coastal ecosystem that is both submerged and above water depending on tide level, is one of these habitats, and acts as an ideal location for barnacles to settle. During high tide, barnacles open their shells and filter the water for food with their legs. When the tide goes out, barnacles close their shells to conserve moisture. Barnacles mostly eat plankton, and are rarely preyed upon in their adult forms, as their shell protects them from most predators (except humans, which eat them in Spain and Portugal primarily). In their juvenile forms, however, barnacles are free floating (prior to settling on a surface), and have numerous predators. Reproduction is simple, and requires the fertilization of a nearby barnacle. A retractable tube is extended to fertilize the other barnacle, and newborn barnacles are released to feed, grow and eventually settle on a new surface.
(a-z-animals.com/animals/barnacle/)
(<a href="https://www.whoi.edu/science/B/people/kamaral/Barnacles.html")
(en.wikipedia.org/wiki/Sacculina)